HiveBrain v1.2.0
Get Started
← Back to all entries
snippetMinor

The amount of ROM needed to implement a 4-bit multiplier?

Submitted by: @import:stackexchange-cs··
0
Viewed 0 times
theneededbitimplementamountrommultiplier

Problem

For a 4-bit multiplier there are $2^4 \cdot 2^4 = 2^8$ combinations.

The output of 4-bit multiplication is 8 bits, so the amount of ROM needed is $2^8 \cdot 8 = 2048$ bits.

Why is that? Why does the ROM need all the combinations embedded into it?

What will be the case with RAM?

Solution

As shown in the figure bellow (general architecture of ROM):

to address 8-bit numbers correctly your ROM size should be: $2^8 \times 8$ bits.

Context

StackExchange Computer Science Q#9471, answer score: 8

Revisions (0)

No revisions yet.